Don't build the 5th windmill until you get the quest to upgrade a windmill to level 5.If you're reading ahead on a quest and see you're going to need flowers, shells, or coral, you can keep your excellent packages unopened until that point in the quest.If you need flowers, shells, or coral, you can send Sand Castles to Naomi (or another player), and receive an 'excellent package' in return.If you send a pearl to someone, it doesn't cost you a pearl. Free gifts don't cost anything except a few clicks.(If you turn in 400 and then the quest ends before you finish, you lose those 400 fiddly bits) That way, If you don't finish the Science Boom quest this time, it will be easy to finish it next time it comes around. Don't turn in event-quest fiddly bits until you have 100% of the fiddly bits needed for a quest step.

Plus, there a quest to build it, and a quest to collect income from it after you build it so it's much cheaper than it appears. It's one of the best income buildings for a low-level player, and you'll need it for quests later. If you're thinking about buying land, it may be a good idea to wait for a sale.

20% off coin, and 30% off crystal purchases.

There's a land-sale every two weeks (approximately).

If you're doing a major quest, read about it on this wikia.

Down near the bottom, there's an option for 'purchase for crystals with no confirmation' - uncheck that option.

Click on the Head in the upper left of your screen.

Turn off 'Purchase for crystals with no confirmation'.

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